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There is a clutch booster underneath the plenum that would have air going through it, although on that video, it sounds more like a harmonic ringing to me...

Could be the clutch bearing but really not sure.

What clutch do you have?
 

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It sounds like a vacuum leak from the clutch booster push rod seal.
I note the sound stops yet your foot hasn't moved from the pedal. Do you notice if the pedal effort become harder at this time?
The clutch and brake boosters take vacuum from the same source but the clutch has a restrictor in the line, so perhaps the leak is greater than the vacuum that can be supplied.
They're available new or can be overhauled but access is difficult.
 

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Discussion Starter · #4 ·
There is a clutch booster underneath the plenum that would have air going through it, although on that video, it sounds more like a harmonic ringing to me...

Could be the clutch bearing but really not sure.

What clutch do you have?
Not really sure to tell you the truth. The guy I bought it from said it was already installed when he bought it. The video changed the noise (not sure why) but its definitely an air sound. Most times when it happens its a fluttering squeak, I just so happen to catch a steady one on vid.
 

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Discussion Starter · #5 ·
It sounds like a vacuum leak from the clutch booster push rod seal.
I note the sound stops yet your foot hasn't moved from the pedal. Do you notice if the pedal effort become harder at this time?
The clutch and brake boosters take vacuum from the same source but the clutch has a restrictor in the line, so perhaps the leak is greater than the vacuum that can be supplied.
They're available new or can be overhauled but access is difficult.
To answer that question...yes. The pedal pushes back on my foot like it has pressure built up behind it, then it usually squeaks a little louder real quick & relieves the pressure resuming normal operation (all without me moving my foot).

So you think changing out that restrictor would help?
 

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No the restrictor in the clutch feed is there so the brake booster will always have priority. (for safety)
I think you need a new/reconditioned clutch booster.
It's a reminder that 25 year old parts eventually wear out.
Also makes you think about other parts, brake booster, brake hoses, fuel hoses………$$$$$$$
 

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Discussion Starter · #7 ·
No the restrictor in the clutch feed is there so the brake booster will always have priority. (for safety)
I think you need a new/reconditioned clutch booster.
It's a reminder that 25 year old parts eventually wear out.
Also makes you think about other parts, brake booster, brake hoses, fuel hoses………$$$$$$$
Word. Sounds like a good fix. I'll try it & see if it fixes the problem. Thanks for the help.
 

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From the info you've described, bleeding will do nothing for a vacuum leak in the booster.
That expensive piece of alloy would seem to be a spacer such that the booster can be removed.
 

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I presume firstly you'd disconnect the vacuum hose to the clutch booster, plug it, start the car to check if there's no longer any noise.
 

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Discussion Starter · #13 ·
I presume firstly you'd disconnect the vacuum hose to the clutch booster, plug it, start the car to check if there's no longer any noise.
Sorry been out of it for a while...which side should I plug up from? Be easy I'm a noob. Lol
 
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